在输配分离后,供电公司需向电力交易中心(Power Exchange)购买电量,其目标是以最小风险获得最大收益,本文研究其如何确定最优购电量的问题。在假设用电需求量为随机变量的基础上,根据其物理意义构造概率分布密度,并对供电公司的收益与风险进行分析;采用期望-方差分析法分别在有、无风险因素条件下和兼顾风险、收益因素条件下构建供电公司最优购电模型,并通过无约束极值法对其进行求解。最后通过算例分析说明由本模型求解得出的最优购电量与供电公司的风险偏好有关,对供电公司的购电策略具有一定的指导意义。
Under transmission and distribution separation condition,power-supplying companies needed purchase electricity from power exchange and its goals were to make their risks minimum and their income maximum. How to ensure the optimal purchase electricity of power-supplying companies is researched in this paper. Suppose electricity is a random variable,the probability distributing functions are built according to its physical characteristic and the income and risk of power-supplying companies are analyzed. respectively The optimal purchase electricity models are established respectively with expectation-difference method under unconsidering or considering risk factors and both considering risk factors and income factors,which can be solved by no restraint extremum method. At last the example shows that the optimal purchase electricity by the models are concerned with risk leaning of power-supplying companies,which have some direction meaning on its.